Needle-clamp for sewing machines



Jan. 31, 1933. A. GR-IEB I 1,896,047

NEEDLE CLAMP FOR SEWING ,MACHINES Filed April 24,. 1931 1 41 gunman! WM wesm l atentecl Jan. 31 1 933 f j UNITED STATES PATENT; OFFICE A FRED GRIEB, E ELIZABETH, N w IEBSEIASSIGNOB mo THE srNGER MANUFACTUR- ING COMPANY, oEELIzAEE'rn, NEw JERSEY, A CORPORATION" or NEW JERSEY NEEDLE-CLAMP Eon sEwmG. MACHINES Application filed April 24,

This invention relates to devices for clamping the needle of a sewing machine in working position relative to the needle-bar and. has for an object to provide a needleclamp which is simple in construction, inexpensive to manufacture and easy to assemble,

and which will securely clamp the needle yet left or,.in other words, withthe long grooved side of the needle-blade toward the set-screw and the short grooved side of theneedleblade away from the set-screw.

The invention comprises the devices, combinations and arrangements ofparts herein} after described and claimed.

Thefeatures of the invention and the advantages attained thereby will be readily understood by those skilled in the art by the following detaileddescription of a pre ferred embodiment of the invention illustrated: in the accompanying drawing, in which Fig. 1; is a front side elevation of the lower end-portion of the needle-bar and the needle-bar housing head of the sewing machine, with the needle-clamp carried by the needle-bar. Fig. 2 is a vertical section through the device. Fig- 3'is a section on the line 3-3 of Fig. 2. Fig. 4 is a' section of the band element only of the needle-clamp on the line 3-3 of Fig. 2. Fig. 5 is a sectional View ofthe needle-bar only, on the line 3 3 of Fi 2.. Fig. 6-is a; perspective view of the need e-clamping gib. Fig. 7 is an elevation or outer face, view of the gib as applied to-the needle-bar. Fig. 8 is a side elevation vof the lower end-portion of the needlebar. Fig. 9jis a front elevation, partly in section, of the lower end portion of the needle-bar, Fig. 10 is a sectional view similar to Fig. 2 showing the parts displaced from operative position in the process of disassembling 'the device. Fig. His :1. perspec- 1931. Serial No. 532,440.

tive view of the sewing machine needle shown in Figs. 1,2 and 3'. i y

1 represents the lower portion of the needle-bar housing head of the sewing machine which is formed asus ual at the free end of the sewing machine gooseneck. Mounted in the head lie the reciprocating needle-bar 20f cylindrical'form having in its lower endwise engagement with the bottom wall 3" of the groove 3. A stop-pin 7 is positioned in the groove 3 to properly locate the upper end of the needle relative to the needle-bar.

Embracing the recessed lowerend of the needle-bar 2 is the clamping band Shaving a lateral screw-threaded aperture receiving the set-screw 9. The proximate surfaces of the needle-bar 2 and clampingbandS" are formed with coaxial opposed cylindrical apertures 10 and 11 which receive the enlarged cylindrical head 12 of the needleclamping gib 13, the lower end-portion 14 of which extends below the lower end of the needle-bar 2 and is bent'tothe form of a thread-guiding hook, The enlarged head 12 of the gib is adapted to be engaged by the inner end of the set-screw 9, as shown in Fi 2 and 3, and forced against the shank 4 of El e needle 5, thereby clamping the latter securely, in position in the recess or groove 3. Since the enlarged head 12 of the gib is partially received in each of the transverse coaxial recesses 10' and 11 of the needle-bar 2 and clamping band 8, respectively, it serves to lock these two parts together and to prevent relative displacement of such parts from their respective operative positions.

The lower. end-portion of the needle-bar 2 is slabbed ofi or cut away at .15 to clear the enlarged head 12 of the gib when the latter is shifted as far as possible into the recess 11 in the clamping band 8. The gib and clamping band may thus be unlocked and removed 3 from the needle-bar 2, as shown in Fig. 10.

= 1 needle bar.

This unlocking of the parts may be efiected by loosening the set-screw 9 and by engaging the exposed lower end-portion 14 of the gib and shifting the gib toward the set-screw 9 to disengage it from the aperture 10. The gib 13 serves to distribute the pressure of the set-screw 9 over a considerable portion of the length of the needle-shank 4L and effects a more secure grip of the needle than would be effected by the end of the set-screw only, were the latter allowed to directly engage the needle-shank. The side-wall portions of the recesses 10 and 11 which cooperate with the enlarged head 12 of the gib to prevent movement of the band 8 lengthwise of the needle-bar, may be described as upper and lower locking-wall-portions. It is not essential that the head 12 of the gib be cylindrical or that the recesses 10 and 11 be circular, as the desired locking-wall-portions may obviously be provided with various shapes.

It is the standard practice to provide a long groove 5' on one side of the blade of a sewing machine needle and a short groove 5 on the.

opposite side adjacent the eye 5 These grooves are thread-clearance grooves. The sewing machine loop-taker always takes the needle-loop from the short-grooved side of the needle. To. insure precision in the location of the needle relative to the looptaker, it is the practice to slab the shank of the needle on the short-grooved side of the latter, as indicated by the numeral 6. The

1 slabbed side 6 of the needle shank is clamped against a seat fixed on the needle-bar. With needles of various sizes afixed relation or spacing is maintained between the plane of the slabbed face of the needle shank and a parallel plane tangent to the short grooved side of the needle-blade, so that a standard clearance is provided between the sewing machine loop-taker and the needle-blade for all sizes of needles.

Various sewing machine attachments, such as rufiling and buttonholing attachments, are provided with operating levers having forked ends adapted to embrace the usual needleclamp set-screw at the right hand side of the The position of such set-screw should, therefore, not be disturbed.

The present improvement provides for the secure clamping of the standard sewing machine needle in a position reversed from its usual position, for'cooperation with a looptaker having a beak passing to the left of the needle-blade, without disturbing any of the conditionsor relations above referred to.

Having thus set forth the nature of the invention, what I claim herein is 1-- 1. A sewing machine needle-clamp comprising, a needle-bar formed in one end with a needle-shank-receiving recess, a clamping band embracing the recessed end of the needle-bar, said needle-bar and clamping band having in their proximate surfaces opposed gib-receiving apertures, means for locking said band against movement endwise of the needle-bar comprising a gib seated in said opposed apertures, and a clamp-screw carried by said band and adapted to engage said gib and force the latter into clamping engagement with the shank of a needle seated in said needle-shankaeceiving recess, said of the needle-bar, the transverse aperture in the needle-bar being in communication with said needlesharrk-receiving recess, a locking gib seated in said opposed apertures, and a clamp-screw carried by said band in position, to engage said gib, said gib being movable out of the gib-receiving aperture in the needle-bar to unlock said band for removal from the needle-bar.

3.. A sewing machine needle-clamp comprising, a. needle-bar formed in one end with a needle-shank-receivingrecess, a clamping band embracing the recessed end of the needle-bar, said needle-bar and clamping band having in their proximate surface-portions opposed gib-receiving recesses defining upper and lower locking-wall-portions, a lockmg gib in said recesses in engagement with said locking-wall-portions, and a set-screw separate from said gib'and carried by said band and adapted to engage said gib, the

recess in said clamping band being deep enough to permit withdrawal of said locking gib from the opposed recess in the needle- 4. The combination with a needle-bar formed at one end with a longitudinal needle-shank-receiving groove open at the side of the needle-bar throughout the length of said groove and having an enlarged portion spaced from the end of the needle-bar, of a needle-clamping gib received in said groove and having an enlarged head partially received in the enlarged portion of said groove, a clamping band embracing said needlebar and having an inner recess receiving a portion of said enlarged head, and a set-screw carried by said band in position to bear upon said gib, the head of said gib being movable out of the enlarged portion of said groove in a direction transverse to the longitudinal axis of the needle-bar to unlock said clamping band for removal from the needle-bar.

5. A needle-clamp for sewing machines comprising, a needle-bar formed at one end with a needle-shank-receiving groove widened at one point to form a cylindrical recess the axis of which is transverse to the axis of the needle-bar, a clamping band embracing the grooved end of the needle-bar and formed with an inner cylindrical recess coaxial with said first-mentioned cylindrical recess, a cylindrical gib disposed in said recesses, a set-screw carried by said clamping" band and adapted to engage said gib, said gib having a shank-portion extending longitudinally of the needle-bar and beyond the end of the latter.

6. A needle-clamp for sewing machines comprising a needle-bar formed at one end with a needle-shank-receiving groove widened at one point to form acylindrical recess the'axis of which is transverse to the axis vof the needle-bar,-a clamping band embracing the grooved end of the needle-bar andformed with an inner cylindrical recess coaxial with said first-mentioned cylindrical recess, a cylindrical gib disposed in said recesses, a set-screw carried by said clamping band'and adaptedto engage said gib, said gib having a shank-portion extending longitudinally of the needle-bar and beyond the end of the latter, said shank portion having a hooked extremity constituting a needlethread guide. a g a In testimony whereof I have signed my name to this specification. ALFRED GRIEB. 

